The present invention relates to a navigation system for a vehicle which provides route guidance to an input destination, along a preset route.
A vehicular navigation system is a system by which a route to a destination from the present position of the vehicle or from a specified departure point is searched based on input data such as destination data, and route guidance is provided based on an optimal route determined by the search, thereby providing the driver with information regarding the determined ("optimal") route to the destination, as the vehicle is driven along that route, a route with which the driver may not be very familiar. In the conventional type vehicular navigation system, data for the estimated present position of the vehicle on a road is obtained from the stored map data by map match processing based on parameters detected by various sensors in a present position detecting unit. Based on the present position obtained by this processing, information pertaining to the next intersection or the next branch point is output, e.g. by an arrow on a display or the like, at a point a given distance in advance of the intersection where the vehicle should be turned to the right or left or after passing through an intersection.
However, in the conventional type navigation system as described above, when the vehicle is driven on a road which has two or more lanes and the vehicle is to be turned right or left at an intersection, the driver often does not know if the vehicle is currently in a right turn lane, a straight ahead lane or a left turn lane. The driver often becomes aware that the vehicle is in a straight ahead lane only immediately before the intersection and may hurriedly try to change lanes into a right turn lane or into a left turn lane or find that he or she cannot change lanes.